My father was air aircraft maintenance manager who rose up the ranks from the USAF to a union mechanic at an airline servicing 707s, 747s, and A300s.
He told me from the beginning not to do any maintenance on equipment without the service manual. So for years and years, for each vehicle I purchased, the next purchase was the factory manual. My ‘85 Dodge Ram W150. My ‘75 Dodge B200 van. My ‘74 Dodge Power Wagon W100. My ‘97 Suzuki VZ800. My ‘07 Harley FXSTC. You get the point. Very detailed manuals from the manufacturer for under $100.
I just bought a used ‘13 (no longer called Dodge) Ram 1500. No physical manual available. You need to get a website subscription to access the online “manual” for that vehicle... for $2000... per year.
Nuts!
Nuts!
I know! Was going to mention this to HYPOCRACY and The Duke when they spoke of collecting manuals for a repair business.
Whenever I stop by an auto parts or thrift store I keep an eye out for the end-consumer Haynes manuals covering makes and models my friends or myself may have - but they don't compare to the in-depth databases those subscriptions provide.
But...YouTube or the internet has saved the day more times than I can recall. It's like a crap shoot but far better than being at the mercy(lessness) of auto repair shops.